powder coating spray 3

The following are the main functions of the equipment and the important parameters are 

briefly introduced as follows:

1 spraying host

The use of the market on the use of the 

spraying machine is dispersed, and some are combined. No matter what mode, the function is 

the same: the powder coating is uniform, and the surface of the metal work piece is 

absorbed. The main function of high voltage electrostatic generator is to produce high 

voltage electric charge, and the zero potential of the workpiece to produce the potential 

difference, the formation of powder coating particles of the main power. The general high 

voltage generator input voltage 220V (or input 24V or 36V) after several times of high 

frequency oscillation, voltage amplification, the output voltage can be as high as 50 

100KV, but under normal conditions (non short-circuit state) output current is only 10 

20uA, no damage effect on the human body. When the normal work will be adjusted to 45 50KV 

high pressure spray gun - powder coating can make good adsorption (the workpiece hanging 

device should be well grounded, R is less than or equal to 4 ohms), such as the second 

additional spraying voltage to 60 70KV (or the preheating workpiece after spraying), 

otherwise it is not easy to powder.

The gun is a key component for powder coating by powder 

barrel gun body must reach the workpiece, good insulation properties, when the workpiece 

from the nozzle distance should be maintained easily between 120 - 180mm, according to the 

different work piece to select a different spray diffusion body is fixed on the gun head to 

achieve uniform atomization. If the distance is too close to the workpiece surface coating 

caused by short circuit arcing, the breakdown point, affects the coating effect; distance 

too far is not easy to absorb powder. When spraying gun must be kept with the workpiece 

perpendicular to the plane, and the moving speed of uniform speed is 0.1 M / s, the 

vertical distance without gaps, but the spray and spray leakage. The powder line length of 

3 - 5 meters, high voltage cable should be well insulated, do not cross docking. In the 

production process of the operator should wear conductive shoes, banned under the pad 

insulation board operation.

Powder feeding barrel is the main equipment to influence the 

amount of powder and atomization during powder spraying. On the market the use of flow 

boiling for powder barrels, usually into powder coating of volume of 2/3 barrels of 

production, adjust the boiling pressure (also called flow pressure) in 0.05 - 0.08Mpa, 0.08 

- 0.12Mpa adjust the air pressure, the powder supply generally between 80 - 150g/min, 

(according to the workers skilled degree and shape of the workpiece and the difficulty of 

adsorption and). If the powder in the powder barrels to add recycling, must be over 180 

after the sieve to add, add a proportion of the recovery and three new powder mixed as 

easy. Production must be used to clean up the powder in the powder barrel, to prevent the 

powder damp or micro hole plate damp blockage. The control system mainly includes 

electromagnetic valve and pressure relief valve, control for powder and air links and 

broken through the handle switch.

2 spray chamber

Spray chamber is the main equipment to make 

the work piece to be coated on the surface of the workpiece, it is required that the height 

and the opening of the workpiece are easy to operate, and the less the opening is, the 

better.

3 Recovery Unit

At present on the market recovery device generally has two kinds, the 

traditional old-fashioned primary recovery and two recovery; a recovery that is the cyclone 

recovery, through cyclone recovery, at the bottom left a lot of recycling powder, the air 

is discharged into the two recovery device containing powder. Two recovery device is 

composed of a filter bag and a vibrator, the air discharged through the filter bag wall, 

superfine powder (only a small amount, about 2 - 5%) at the bottom of the bag. The old 

recycling device has the disadvantages of large floor area, difficulty in cleaning and 

changing of powder.

The novel recovery device is improved on the basis of the old recovery 

device. The two recovery and a recovery back, let the air into the bag containing powder or 

core wall, pumping air leaving the recovery powder (until the spray room), every two to 

three minutes by the anti pulse device form air reverse blowing and finish in a few 

seconds, the powder adsorbed on the earthquake the bag or filter on to spray chamber, and 

then repeat the initial working condition. Pulse back blow when several filter filter, it 

will not make the dust overflow. Most of the filter paper made of paper, coated with 

organic resin, the surface is smooth, not easy to stick powder, filter paper strength, good 

permeability, outside the metal mesh protection, can be used for a long time.

Whatever the 

way of recycling, ensure indoor dust can not overflow for the purpose must be, general 

spray room should be 0.05 to form a negative pressure of about 0.09Mpa, the spray room at 

the opening of the air velocity should be controlled within 0.5 0.6m/ seconds, in order to 

achieve this purpose.

4 delivery system

Transport system mainly includes conveyor chain and 

truck etc.. Large automatic spraying production line with the suspension conveyor chain 

more directly to the workpiece to the spray chamber, after spraying directly to the curing 

furnace, workers are only responsible for unloading, bear fruit. This kind of conveyor 

chain requirements to adjust the motor speed, to cure time 20 minutes, at the same time, 

there is enough time to spray. The conveyor chain is the key to ensure the smooth 

transmission of good lubrication good coating, must use high-temperature lubricant (MoS2 or 

high calcium base grease), small production line is often used in manual operation, after 

spraying hanging in a cargo car into the curing furnace. The freight car transportation 

requirements promote smooth, convenient, suitable for low hanging workpiece can.

5 curing 

device

At present, the electrostatic powder coating curing device used from the structure 

divided into two kinds of cave and tunnel, tunnel type curing oven is suitable for large 

batch, variety of fixed and single product. Equipped with automatic conveyor chain, large 

output, high energy consumption, suitable for continuous uninterrupted production, and cave 

type curing oven is to the contrary, it is by small and medium enterprises like individual. 

From the thermal energy is divided into fuel.